Fig. 6

Antigen re-challenge results in CAR expression reduction. Sorted CD8⁺ CAR^hi and CAR^lo cells were assayed for EGFRt surface expression after 24 h of co-incubation. A small fraction of CAR^hi cells becomes CAR^lo upon antigen re-challenge, while a significant reduction in CAR expression is observed among CAR^lo cells after stimulation